potter



2 Sheets-.-Sh'eat 1'.

(N0 Model.)

A POTTER Conoave for Thrashng Machines.-

Patented oct. 19,1880.

NJFETERS. PHOTO-LJYMDGRAPNE (No Model.) zsneenssneeu2. A.- POTTER. Concave for Thrashing Machines.

Patented Oct. 19,1880.

UNITED STATES PATENT Trice,

ALBERT POTTER, OF SPRINGVATER, NEV YORK, ASSIGNOR OF ON E-HALF OF HIS RIGHT TO DAVID CURTIS, OF SAME PLAGE.

-CONCAVE FOR THRASHlNG-MACHINES.

SPECIFICATION forming part of Letters Patent No. 233,544, dated October 19, 1880.

Application filed May 21, 1880.

To all whom 'it may concern:

Be it known that I, ALBERT POTTER, of Springwater, in the county of Livingston and State of New York, have inventedcertain new and useful Improvements in Ooncaves for Thrashing-Machines; and I do hereby declare that the followingis a full, clear, and exact description of the invention, which will enable others skilled in the art to which it appertains 1o to make and use the same, reference being had to the accompanying drawings, which form a part of this specification, and in whichj Figure 1 is a perspective View of a concave embodying my improvements. Fig. 2 is a vertical cross-section taken through line :v x in Fig. 1, showing the adjustable teeth and teeth-bars in their lowered position. Fig. 3 is a similar view, showing` the adjustable teeth and teeth-bars injtheir elevated position, and 2o Fig. 4 is a perspective view ot' the concaveheads and frame, the curved beds or breasting, as well as the adjustable toothbars having been removed.

Similar letters of reference indicate corre- 2 5 sponding parts in all the figures.

My invention relates to th rashin gmachines and it eonsistsin an improved construction and combination of parts of the concave or curved bed in which the thrashing-cylinder works,

3a substantially as hereinafter morefully set forth, and particularly pointed out in the claims.

In the drawings, A A are the heads of the concave, which are, bypreference, of cast-iron, and provided each with an upper and a lower 3 5 curved groove or channel, denoted, respectively, bythe letters a and b, which are united by cross-grooves c.

The breasting \is made in three separate parts-viz., `an open frame or plate, C, and 4o two bed-plates, D E, all of which are curved to it the upper curved channels, a, inthe heads A A, into which they are inserted. Each of the bed-plates D Eihas along its outer edge a row of stationary teeth, d parallel to and alternating with which plateD has a single row of slots or apertures, f, w'hile plate E has a double row of slots, g h, the slots composing one row being set a little to one side of those composingthe other row, in such a manner that 5o the slots composing the row farthest from the (No model.)

row of stationary teeth c of plate E shall be opposite to orinaline with the stationary teeth d of plate D. These breast-plates O D E are preferably made ot' cast-iron of good quality.

Inserted with their ends into the lower curved channels I) of the heads A A are three parallel wrought-iron bars, F G H, provided with stout tapering teeth j" g' it', of the same material. Each of these bars is made with bolsters upon its under side, one at each end, 6o which rest upon or bear against shoulders i upon curved bars I K L, one end of each of which said bars is inserted into a slot or mortise in a cross-bar, M, which unites the two heads A A, and is prevented from coming out by a lock-bar, N, nutted upon bar M.

Each pair of curved bars I I, K K, L L is united at its opposite or free end by a crossbar, denoted, respectively, by I, K', and L', thus forming three independent rock-frames 7o or cradles, I I I, KK K, L Ll L, arranged one within another, and all hinged at one end upon the bar M, while their outer free ends are supported upon screw-bolts O O O2, which work in a plate or bar, P, uniting heads A A opposite to the bars M and N. It follows that by adjusting these bolts their respective cradles may be raised or lowered at will in respect of the toothed and slotted bed-plates D E, with reference to which the cradles and toothed 8o bars F Gr H, resting tl1ereon,are so adjusted that the teeth f of bar F will project into the slots j' in the innermost bed-plate, D, those of the intermediate bar G into the row ot' slots g in plate E, while the teeth h' of the outer 85 bar, H, will register with slots 7L in the same plate E.

It will thus be seen that either one or all of the adjustable rows of teeth f g 7L may be brought into or out of play at will, and with- 9o out stopping the machine, by simply lowering the screw-bolts O, O', or O2, as the case may be, or either one or all of the toothed bars F GH may be entirely withdrawn from the machine if any one of the adjustable teeth should become bent or broken.

By this improvement the concave maybe adjusted, while the machine is in full operation, to thrash any kind of grain fed into it, by a simple adjustment of the teeth, which, it will 10o be seen, does not require the removal of the concave-heads or bed-plates, or any interference with them at all. The adjustable teeth, when inserted in the manner described into their respective bed-plates, serve to brace and strengthen these; and if, by accident, any one of them should break off at its base, it cannot slip out of its slot in the bed-plate on account of its tapering shape, which corresponds to and lits closely into the tapering slot in the bed-plate, through which it projects.

In thrashing-machines as heretofore constructed, in thrashing wheat many of the kernels are broken by the teeth of the concave; and if,to obviate this, the teeth (as in some cases) are made yielding, the thrashing, while not breaking the kernels, is apt to beimperfect g butbymyimprovement, by lettingdown(by operating thc screw-bolt 0') the middle row, g', of adjustable teeth, sufficient space is provided between the remaining teeth for the escape of the kernels without cracking them. By raising the middle row, g', and lowering the third ro w. j, the space between the teeth is lessened, and, while adapted for other kinds ot' smaller grain, would be apt to crack wheat. Whatever adjustment of the teeth is desired may be effected without stopping the feeder for a moment, and the improvement may be applied to any thrashing-machine by removing the old concave and substituting new heads with their appurtenances, according to the foregoing specification.

It is obvious that I do not conne myself to three adjustable tooth-bars, and may use more or less, according to circumstances; but

I claim as my invention, and desire to secure by Letters Patent of the United States- I. In a thrashing-machine concavefa bed or bed-plate having two rows of teeth arranged opposite to and alternating with each other, and two or more intermediate rows 0r series of alternating slots, in combination with a corresponding number or series ot' adjustable toothed bars arranged below and registering with the several corresponding series of slots in the bed-plate, so that by adjusting the bars their teeth-may be raised or lowered through the respective slots in the bed-plate with which they register, substantially as set forth.

2. In combination, the grooved or channeled heads A A, removable breasting-plate C, and bed-plates D E, having teeth d e and slots f gli, hinged frames I I I, K K K, L L L, supporting the toothed bars F Gr H, and screwbolts O O O2, for eecting their vertical adjustment in respect of the slotted bed-plates, substantially as set forth.

In testimony that I claim the foregoing as my own I have hereto affixed my signaturein presence of two witnesses.

ALBERT POTTER.

Witnesses CHARLES WENNER, HENRY '.I. GRovER. 

